<DOCUMENT>
<TYPE>EX-21
<SEQUENCE>3
<FILENAME>d95136ex21.txt
<DESCRIPTION>SUBSIDIARIES
<TEXT>
<PAGE>
                                                                      EXHIBIT 21


                         SUBSIDIARIES OF THE REGISTRANT


<Table>
<Caption>
                                                            PERCENTAGE OF
                                             ORGANIZED    VOTING SECURITIES
                                               UNDER           OWNED BY
                                              LAWS OF        CULLEN/FROST
                                           -------------  -----------------
<S>                                        <C>            <C>
The Frost National Bank                    United States         100%

Main Plaza Corporation                         Texas             100%

Daltex General Agency, Inc.                    Texas             100%

The New Galveston Company, Inc.              Delaware            100%

Cullen/Frost Capital Trust I                 Delaware            100%

Frost Insurance Agency                         Texas             100%

Frost Securities, Inc                        Delaware            100%
</Table>


</TEXT>
</DOCUMENT>